Chemiluminescent systems which produce light upon admixture of two components are well known. The two components are kept separate until light is desired. At the desired time, the two components are mixed and light is produced. The intensity, duration and color of the light will depend on the ingredients of the two components.
The first component is an oxalate component which comprises an oxalate ester. The second component is an activator component comprising a peroxide and a catalyst. The system will also include one or more fluorescers which may be present in either component. The fluorescer(s) are typically selected on the basis of the desired coloration of the light.
The chemiluminescent system must also include one or more solvents. Typical prior art chemiluminescent systems require the presence of one or more solvents for the oxalate component and one or more solvents for the activator component. The solvents selected for the two components may be different but they should be miscible.
The solvent(s) selected for the oxalate component must dissolve the selected oxalate ester, and the solvent(s) for the activator component must solubilize the selected peroxide and the selected catalyst. If the fluorescer is present in the oxalate component, the solvent selected for the oxalate component must solubilize the selected fluorescer as well as the selected oxalate ester. If the fluorescer is present in the activator component, the solvent must solubilize the selected fluorescer, the selected peroxide, and the selected catalyst.
Typical solvents disclosed in the prior art for the oxalate component include esters such as ethyl acetate, ethyl benzoate, butyl benzoate, dimethyl phthalate, dibutyl phthalate, dioctyl phthalate, methyl formate, triacetin, diethyl oxalate and dioctyl terphthalate; aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and butylbenzene; chlorinated hydrocarbons such as chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, chloroform, carbon tetrachloride, hexachloromethane and tetrachlorotetrafluoropropane; ethers such as a propylene glycol dihydrocarbyl ether, e.g. dipropylene glycol dimethyl ether, 2-ethoxyethanol, diethylene glycol butyl ether and propylene glycol n-propyl ether.
Typical solvents disclosed in the prior art for the activator component include alcohols such as t-butyl alcohol, ethanol, n-octanol, 3-methyl-3-pentanol and 3,6-dimethyloctanol-3; esters such as ethyl acetate, ethyl benzoate, dimethylphthalate, dibutylphthalate and methyl formate; and ethers such as diethyl ether, diamyl ether, tetrahydrofuran, dioxane, diethylene glycol monobutyl ether, perfluoropropyl ether and 1,2-dimethoxyethane.
Prior art disclosures of chemiluminescent systems utilizing the solvents listed above may be found in the following US patents and published patent applications: U.S. Pat. Nos. 3,816,326; 4,678.608; 4,717,511; 5,281,367; 5,597,517; 6,126,871; 20050098766; 20050224768; 20080246009; and 20110084243.
The organic solvents listed above are generally disadvantageous due to environmental, health, safety, nuisance and malodorous issues. It would be most desirable if a water-based chemiluminescent system could be provided such that the solvent for the activator component comprises water and the solvent for the oxalate component comprises a minimal amount of an organic solvent that is acceptable from an environmental, health, safety, nuisance and odor point of view.
Prior to the present invention, the use of water as the solvent for the activator component was not considered possible. It is well known that, upon admixture of the oxalate and activator components, the water would degrade the oxalate ester present in the oxalate component to the point that the intensity and duration of the light produced by such a system was seriously diminished. Accordingly, a water-based system was deemed commercially useless.